Fall Colloquium Honoring Marissa Weichman

My lab pursues new schemes to steer chemistry using light and new spectroscopic methods to better probe the structure and dynamics of complex chemical systems.
In this talk, I will detail our recent work to demystify how molecules behave under strong light-matter coupling to an optical cavity. Molecules under these conditions have been reported to demonstrate distinct reactivity from molecules in free space, though the mechanisms of these phenomena have been a subject of great debate. I will discuss how we have pioneered the first experimental platform for gas-phase molecular polaritons and how we have examined the ultrafast chemistry and dynamics of condensed-phase molecules under vibrational and electronic strong coupling. I will show how classical cavity optics serves as a unifying language and interpretative tool for the linear and nonlinear spectroscopy of polaritonic systems. This framework ultimately permits a comprehensive understanding of our experimental results and of molecular polariton behavior more broadly.

While our work in polaritonics harnesses optical cavities to reach the strong coupling regime, we also deploy cavities to enhance light-matter interactions for high sensitivity precision spectroscopy. I will mention our efforts to deploy cavity-enhanced spectroscopy to solve key problems in laboratory astrochemistry and aerosol science.